[taude]

I'm not sure I fully understand your use case? Why would you be looking at the map in the middle of a fast descent like that. Were you already not aware that you'd have to slam your brakes on halfway down the hill for a right-turn before you even started the descend?

And I think the argument holds even less water in a fast group ride. Does no one in the group, especially the people at the front know where the group ride is going? If everyone is half lost, surely it'd be going pretty slow while someone calibrated where the group should be going....

[karamanolev]

1. On a fast descent I like to know what the turns coming up look like. Also, sometimes we follow the main road, sometimes we turn out at some point. If it's a 100mi ride that was planned online, even the planner doesn't know it by heart. You have to look occasionally.

2. No, you're not aware when you have to slam on your brakes. The descent can be 10 minutes long at a high speed. You don't know every single corner by heart. You look at the map.

3. The people at the front know where we're going, but sometimes they miss things. It's nice to shout things at them when they do. They also rotate. I know there's a bit of gravel on this road, but they don't. I tell them. I know because I know we're passing town X or side street Y.

4. Even in a group, I'd like to know if there's a sharp turn coming, going into the city, etc. I want to know my heart rate, power, cadence, etc. I'd like to know how long the false flat that we're on lasts or when the next climb is coming up.

[talove]

I'll also add, you might be riding brakes preparing for a turn on a descent. Under many road conditions, especially a steep descent, a road bike is much more likely to break traction than a car which can literally be fatal (sliding out into an opposing lane, barrier, or off an edge). Anybody who has descended, even at reasonably safe speeds on a road bike with a bike computer knows it is the safe thing to do.

[kcmastrpc]

If I'm going down a relatively new descent, I'll use the bike map computer to visually confirm if there is a sharp turn or other hazard that might be on a blind corner (side roads connecting). I only need to glance at it, but it's very useful.

[karamanolev]

Yep. Can confirm. Quick glance, tells you what you need to know. Car drivers (sad to admit myself included) take their eyes off the road for much much longer. What I'm saying is that you do look at the bike computer.